Fiber optic applications using optical fiber connectors and adapters often require the identification of specific optical fibers during installation, interconnection, and maintenance testing. For example, referring to FIG. 1, the typical fiber run for a user utilizing a fiber optic connection might extend from a source or central office to a cross box, from the cross box to a curbside access terminal, and finally from the curbside access terminal into the user's home or office. Within such a system, connections of the optical fibers between the various intermediaries are typically accomplished through the use of fiber adapters mounted within patch panels, cabinets, or racks. Each of the panels, cabinets, or racks typically includes a large number of optical connector adapters or ports all aligned along a densely packed interface in which fiber connectors can be coupled. Thus, because of the sheer number of cables and the small area in which the cables are packed, as well as the distances and interconnections required of fiber optic applications, the problem of uniquely identifying specific connectors becomes clear. Further, as patch panels become increasingly smaller and, in turn, fiber optic cabling becomes increasingly more densely packed, effective identification of individual fibers becomes increasingly more important.
When a specific connector of a panel is needed for interconnection with another connector, visible light from a visual fault locator (VFL) is used to perform optical fiber tracing for connector identification. For example, in the illustration provided in FIG. 1, a technician working in the user's home, attempting to diagnose a cabling or connection problem, can apply the VFL to the terminus of the fiber optic connector. The VFL emits a bright beam of laser light into the fiber via the terminus to send light throughout the length of cable and any subsequently connected cable. Another technician located at the source or central office can then see a visual indication via visible light on a particular port at the central office to thereby discover the corresponding source port. Of course, this process can be replicated for any subset of the fiber run in order to identify subsets of cabling. For example, a technician may wish to identify the cabling subset from the curbside access terminal back to only the cross box. In such a case, the VFL can be applied from the curbside access terminal for visual indication at the cross box.
Dust caps are used to prevent the optical fiber adapters and connectors used in fiber optic applications from being contaminated by dirt, dust, and other particles, as well as to prevent contact with objects that can scratch, chip, crack, or otherwise physically damage the polished core of the fiber. To do so, dust caps typically engage fiber adapters such that the entire adapter is covered. Dust caps are traditionally made of opaque plastic materials, such as, for example, low-density polyethylene materials. Because of the opaqueness of the cover and total coverage over the adapter when engaged, it is impossible to detect the light from a VFL without removing the dust cap. As a result, for panels having a large plurality of ports, the technician attempting to identify a particular cable and associated port must remove many dust caps in order to find the visible light. Not only is removing many dust caps tedious, but removing the dust cap can be risky, as the opportunity for eye damage exists if light is directly viewed through the fiber. Further, removing and replacing dust caps can create an opportunity for dust and other contaminants to reach the polished end of the fiber.
To combat some of these problems, certain dust caps having translucent bodies have been devised. The light from a VFL is introduced to the back side of the translucent dust cap via the connected fiber, which subsequently flows through the body of the cap and into view of the observant technician through the walls of the body. However, such dust caps generally have a dull glow, which can often be difficult to identify in brightly lit environments.
Thus, there remains a need for a fiber optic dust cap that provides for the safe, effective identification of individual fiber optic fibers via a piercing, yet harmless, visual indication without needless removal of the dust cap.